On highway transport trucks and trailers there are wheels that are bolted in place. There have been truck and trailer wheels and wheel assemblies accidentally detaching from the moving vehicle. Once detached the wheels or assemblies will travel unrestricted causing property damage, injury or death.
At present there is no method of restraining accidentally detached wheels or wheel assemblies on transportation vehicles. The standard at present is to rely upon the installation of the wheel and wheel assembly without any secondary restraining mechanism. This system allows for the original installation mechanism to fail totally and still retain the wheel or wheel assembly to the vehicle.
The wheel assembly, when in operation, is a relatively heavy rotating mass that is mounted on an axle, using bearings and a wheel hub. Problems will arise when the wheel breaks or separates from the wheel hub, the wheel bearing and/or wheel hub fail or the axle breaks. In these situations, some or all of the wheel assembly will separate from the vehicle and will not be restrained.
In all of these failing situations, the portion of the wheel or wheel assembly that is detached must move away from the vehicle in unrestrained fashion.
Of background interest are U.S. Pat. No. 2,627,437 of M. H. Toncray et al issued Feb. 3, 1953 and U.S. Pat. No. 5,462,324 of Bowen et al issued Oct. 31, 1995, describing respectively an automobile frame construction and a wheel guard attachment for motor vehicles.